För att enstaka uppmätta grundvattennivåer ska kunna användas för att kartlägga grundvattennivån även i områden där långtidsmätningar saknas behövs en korrektionsmetod. Det övergripande målet med den här studien var att sammanställa och åskådliggöra grundvattennivåmätningar som inkommit till Länsstyrelsen i Uppsala län i samband med vattenskyddsdispenser. Syftet med arbetet var att undersöka hur grundvattennivån fluktuerat i olika jordarter och ta fram en metod för att korrigera punktvis uppmätta nivåer så att de speglar grundvattennivån ett normalår. Det normalårskorrigerade långtidsmedelvärdet på en viss plats ska vara detsamma oavsett om mätningarna av grundvattennivån utförts på våren, sommaren eller hösten och det ska inte heller spela någon roll om mätningarna utförts ett regnigt eller torrt år. Långtidsmätningar av grundvattennivåer i olika jordarter studerades. Fokus låg på grundvattennivåns års- och månadsavvikelse från mätseriens uppmätta långtidsmedelvärde. Utifrån avvikelserna skapades korrektionsfaktorer som adderades till uppmätta punktmätningar av grundvattennivåer. Grundvattennivåer beräknades med den framtagna korrektionsmetoden. Dessa jämfördes sedan mot uppmätta nivåer och grundvattennivåer beräknade med S-HYPE-modellen. Metoden testades även på ett oberoende dataset från Tärnsjö och implementerades på en mindre del av grundvattennivåmätningarna i och runt Uppsala stad. För grundvattennivån i jordarterna sand och grus var variationer mellan olika år viktigast att korrigera, då inomårsvariationerna var små. Grundvattennivåerna i morän varierade kraftigt inom ett och samma år vilket resulterade i att månadskorrektionen var den viktigaste faktorn. Två typer av grundvattenkartor skapades utifrån uppmätta grundvattennivåer. Kartornas utbredning täcker Uppsala stad med omnejd. Den ena kartan visar grundvattennivån som meter under markytan. Den andra kartan visar grundvattennivån som en trycknivå i höjdsystemet RH 2000. / In areas where long-term measurements are missing, a correction method is required in order to map groundwater levels based on single groundwater level measurements. The overall objective of this study was to compile groundwater measurements submitted to the County Administrative Board as part of water protection permit applications. The aim of this work was to investigate how the water table fluctuates in different types of soil and to develop a method to correct particular measured point levels to reflect the water table in an average year. The corrected long-term average value in a specific location should be the same regardless of whether the groundwater level measurements were performed in the spring, summer or autumn, nor should it matter if the measurements were done in a rainy or dry year. Long-term measurements of groundwater levels in different soil types were studied. The focus was the annual and monthly deviation of groundwater levels from the long-term average. Based on the deviations correction factors were created that were applied to the point measured groundwater levels. Groundwater levels calculated with the produced correction model were compared to the measured levels as well as the groundwater levels calculated by the S-HYPE model. The method was also tested on an independent data set from Tärnsjö and implemented on a smaller portion of the groundwater level measurements in and around the city of Uppsala. For groundwater levels in sand and gravel formations, it was important to correct for the variations between years, while the variations within the same year were small. Groundwater levels in till varied widely within the same year, making the monthly correction the most important factor. Two types of groundwater maps were created from measured groundwater levels. The map distribution covers the vicinity of Uppsala city. One map shows groundwater level as meters below surface. The second map shows groundwater level as an elevation above sea level in the height system RH 2000.

Grundvatten och dess varierande nivåer kan potentiellt få en stor inverkan både på byggnaderoch dess omgivning och kan innebära risker som upplyftande krafter, skred och ras. Baseratpå detta är det av vikt att kunna förutsäga extrema grundvattennivåer, kallat dimensionerandegrundvattennivåer. Däremot görs sällan mätningar under en längre tid, vilket krävs för att fastställasannolikheten av en viss grundvattennivå. För att kunna prognostisera den dimensionerandegrundvattennivån har den så kallade Chalmersmodellen utvecklats. Modellen utgår från attsätta korta mätningar från ett grundvattenrör vid en observationsplats (observationsrör) i relation till en lång mätserie från ett grundvattenrör vid en referensplats (referensrör). Enligtmetoden ska val av referensrör baseras på att det är likartade förhållanden mellan de två platserna, att de ligger inom 50 km från varandra och att mätningar i referensröret utförts i mer än 20 år. Denna studie syftar att utreda med vilken tillförlitlighet som Chalmersmodellen kan prognostisera grundvattennivåer som kan förekomma inom en viss återkomsttid. Fokus är på hur valet av referensrör som är placerade vid olikartade hydrogeologiska förhållanden påverkar Chalmersmodellens resultat. Studien utförs som en fallstudie, med utgångspunkt i utbyggnaden av tunnelbanan i Stockholm vid Sockenplan och Station Sofia. Utgångspunkten i Chalmersmodellen är att använda grundvattennivåmätningar från observationsplatsen tillsammans med mätningar från en ostörd miljö vid en referensplats. Beräkningar görs genom att utföra databehandling och beräkningar i Python i enlighet med beskrivningar från Chalmersmodellen och utvärderas genom att jämföras mot en liknande metod kallad extremvärdesanalys. Karakterisering av platserna vid observationsrören och referensrören används för att utvärdera hur stor inverkan olika hydrogeologiska egenskaper (akvifertyp och topografiskt läge) har på beräkningarna av den dimensionerande grundvattennivån. Resultaten visar att Chalmersmodellen generellt underskattar dimensionerande grundvattennivåer. Modellen har även varierande storleksordning av noggrannheten och därmed är det svårt att fastställa förväntad noggrannhet med Chalmersmodellen. Studien visar även att om observationsrör och referensrör är placerade vid en sluten akvifer kan en högre tillförlitlighet förväntas och osäkerheten i tillförlitligheten tycks öka för öppna akviferer. Slutligen om referensrör och observationsrör väljs utifrån att likartade hydrogeologiska egenskaper och samvariation mellan respektive grundvattennivåer, kan högre precision förväntas enligt denna studie. / Groundwater can potentially have a great impact on both constructions and the surrounding areas, and high groundwater levels can involve risks such as uplifting forces and landslide. Due to these risks it is important to predict and estimate the probability of extreme groundwater levels. However, when the necessary long term measurements are not available alternative methods are needed, like the Chalmers model. The Chalmers model is used for calculating extreme ground water levels, by combining a short measurement series from an observation well with the data from a reference well. For the results to be as accurate as possible, the two wells must share similar characteristics. The aim of this study is to investigate the Chalmers model when predicting the groundwater level for a specific return period. Focus will be on how the choice of different reference wells, with different characteristics, will influence the accuracy of the model.  A case study will be conducted on two station sites (Sockenplan and Station Sofia) for the extension of the metro in the southern part of Stockholm, Sweden, upon which the Chalmer model will be implemented. The different characteristics of the obeservation and reference wells are tested to evaluate the accuracy of the model. The accuracy will be evaluated by using extreme value analysis as an alternative calculation model, assumed to be more precise, and compare the difference in extreme groundwater levels. The measurements used as reference in the Chalmers model are public data from The Geological Survey of Sweden, SGU, for groundwater levels. Data processing and calculations are performed in python. This study highlights the difficulties in determining the accuracy of the Chalmers model when predicting extreme groundwater levels, and no specific expected accuracy has been determined. Generally, the model appears to underestimate extreme grounwater levels. Furthermore, if the observation well and reference well are located by a confined aquifer and between inflow- and outflow areas, a higher precision can be expected. The uncertainty of the model increases with an unconfined aquifer. The results also imply that if the reference well and the observation well are selected based on similar hydrogeological characteristics, a covariation of groundwater levels over time and between highest and lowest level, a higher accuracy can be expected.

Grundvattnets kemiska kvalitet påverkas av olika processer i dess närområde, dessa kan vara såväl mänskliga aktiviteter som klimatologiska faktorer. Hur och i vilken utsträckning de påverkar grundvattenkvaliteten kan studeras genom att undersöka utvecklingen av historiska grundvattenkvalitetsdata i relation till förändringar i klimatet. Detta kandidatarbete syftar till att studera hur grundvattnets kvalitet påverkas av klimatförändringarna. Data över ökande och minskande trender i förändringar hos olika kemiska parametrar har bearbetats utifrån material från Sveriges geologiska undersökning från stationer i grundvattenmagasin utspridda i Sverige, detta under åren 1985-2014 samt 1995-2014 i områden där risk för lokal föroreningsspridning är liten. De undersökta kemiska parametrarna är olika salter, tungmetaller, organisk halt och fysikaliska parametrar. De senaste 40 åren i Sverige har präglats av ett varmare klimat med höjda grundvattennivåer, klimatscenarier förutser en liknande utveckling men där grundvattennivåerna kommer sjunka i sydöstra Sverige. Resultatet visar på trender som mest sannolikt beror på minskade deposition av svavel, kväve och tungmetaller sedan slutet av 1970-talet. Mätvärden för sulfat, kväveföreningar, konduktivitet, tungmetaller och pH har minskat, medan dessa för alkalinitet och organisk halt har ökat. Klimatologiska faktorer som har påverkat grundvattnet är en ökad årsmedeltemperatur och förändrade grundvattennivåer, vilket främst syns genom ökande temperatur i grundvattnet samt utspädning av salter och en ökad organisk halt. / The chemical quality of groundwater is affected by different processes in its surrounding. These can be human activities as well as climatological factors. How and to what extent they influence the groundwater quality can be studied by examining the development of historical groundwater quality data in relation to changes in the climate. This Bachelor thesis aims to study how the quality of the groundwater is affected by the climate change. Data of increasing and decreasing trends in changes of different chemical parameters have been processed based on material from the Geological Survey of Sweden from stations in groundwater aquifers spread out in Sweden. The data represent the years 1985-2014 and 1995-2014 and are collected in areas where the risk of local pollution is small. The investigated chemical parameters are different salts, heavy metals, organic content and physical parameters. In the last 40 years, Sweden has been characterized by a warmer climate and higher groundwater levels, and climate scenarios predict a similar development but with a lowering of groundwater levels in south-east of Sweden. The results show trends that most likely indicate a decrease in deposition of sulfur, nitrogen and heavy metals since the end of 1970’s. Measured concentrations of sulphate, nitrogen compounds, heavy metals and also conductivity and pH have decreased, while alkalinity and organic compounds have increased. Climatological factors that have influenced the groundwater are the increased annual mean temperature and variation in groundwater levels, which is mainly evident as an increased temperature in the groundwater, dilution of salts and an increased organic content.

In Southern Manitoba, potato producers are experiencing wetter and drier conditions within the soil profile during the growing season leading to poor quality and inconsistent yields. Russet Burbank Potato cultivar was grown in Southern Manitoba on fine sandy loam soil in a two year (2013-2014) study using two water management treatments: (i) overhead irrigation and (ii) no-irrigation. The main objectives of the study were (i) to assess the impact of overhead irrigation on water table depth and potato yield (ii) to estimate the shallow groundwater contribution to potato water requirement through upward flux (iii) to track the nitrogen dynamics within the potato root-zone under overhead irrigation and no-irrigation scenarios (iv) to examine the effects of no-irrigation and overhead irrigation system at critical growth stages on marketable yield and quality of potatoes. In 2013, water was applied using a linear move irrigation system and in 2014 a rain gun irrigation system was used for the irrigated treatment. Volumetric soil water content, precipitation, irrigation depth, water table depth, nitrate concentration and electrical conductivity in potato root-zone, groundwater electrical conductivity, weather variables, total potato yield, marketable yield, and quality parameters were measured. The total yield was not significantly different between the two treatments in both years. The marketable yield of the irrigated treatment (36.89 MT/ha) was 20% higher (p = 0.017) compared to the non-irrigated treatment (30.74 MT/ha) in 2013. However, no significant difference was found between the irrigated (39.0 MT/ha) and non-irrigated (43.7 MT/ha) treatments in 2014. Potato yields from both treatments were significantly correlated with the average groundwater depth. Water balance analysis within the root-zone during rainy and rain-free periods showed that nitrate rich groundwater may have contributed to some of the crop water demand. The lack of rainfall and high temperature during tuber initiation and tuber bulking stages resulted in the accumulation of high concentration of nitrates within the root-zone by the late release of nitrates from the polymer-coated urea and the upward migration of groundwater containing 55 ppm and 70 ppm of nitrates in the 2013 and 2014 growing seasons, respectively. Overhead irrigation was found to be economically advantageous to produce better quality potatoes with higher marketable yields.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15034号 / 工博第3183号 / 新制||工||1479(附属図書館) / 27495 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 関口 秀雄, 教授 間瀬 肇, 教授 後藤 仁志 / 学位規則第4条第1項該当

The theme of this diploma thesis is the design and assessment of a part of the underground load-bearing structure of the administrative center according to the source material. Emphasis is placed on the design, taking into account the waterproofness of the construction, the so-called white tank. This is ensured by the correct design of the concrete construction of the foundation slab and walls, taking into account the constructional details of the day and expansion joints, the concrete composition and the construction process.

There is an extended concern for how to quantify the fluxes of greenhouse gasses (GHG) and how they are related to climate change and land use. Efforts have already been done, mostly regarding carbon (C) compounds, but there is still much to be done especially to understand regulating factors and interactions with the Nitrogen cycle. NitroEurope is a large project for the integrated European research into the N cycle. This study shares its aim, to improve the understanding the physics involved in the fluxes of the reactive N (Nr). More specifically, the patterns of some physical and biological processes related to Nr have been studied for two wetlands, one in the proximity of Edinburgh and the other in the North of Finland.   A common model setup has been used for both of them, since they are both peat soils. The differences applied to achieve appropriate performances give insights of their nature. The presence of snow is a major factor that governs the behavior of the site in Finland. The scaling of existing models for the estimation of heat transfer in the soil of the Scottish site is also critical, such as its groundwater level. The sites represent different climatic conditions, but for CO2 fluxes they showed similar behavior and response to governing meteorological conditions. Using the GLUE method in combination with a process oriented ecosystem model, some further insights have been gained for the regulation and control of greenhouse gas emissions from the two sites.

Groundwater is a sensitive component affected by climate change. Modelling the dynamics of groundwater levels is inherently difficult particularly as the response to climate change. Given this complexity, most of the current studies using long term groundwater time series were conducted by statistical analysis or using over simplified assumptions to represent the physical processes in hydrological system. With the objective of providing an improved physically based groundwater modelling approach to support climate change impact assessment, a dataset of long term time series of groundwater levels from two different soil types (sand and till) were selected from the Tärnsjö area located in southeast of Sweden. The CoupModel was chosen to perform the simulation since it offers a physically based representation on groundwater recharge processes. A two-step strategy for calibration with first short-term calibration followed by long-term testing was adopted. Simulated groundwater levels followed the general patterns of measured groundwater level dynamics; however, auto-correlations and periodicities were observed in residuals for all sites of which two sandy soil sites with deeper groundwater tables maintained strong auto-correlations in long time lags and an extra 15.4-year periodicity. The long memory of the system rendered it more susceptible to climate change. Uncertainty arises if different initial condition had been applied in short term period calibration.

No ciclo hidrológico, o processo de evapotranspiração (ET) representa a maior percentagem do total de precipitação. As maiores percentagens de ET são encontradas nas zonas ripárias visto a alta disponibilidade hídrica. Embora existam métodos acessíveis para estimativa da ET em zona ripária, como os baseados na flutuação diária do nível piezométrico, poucos estudos têm sido desenvolvidos devido à complexidade teórica da variável, ao elevado custo de equipamentos, e à reduzida largura dessas áreas. Desta forma, o objetivo deste trabalho foi avaliar 10 métodos baseados na flutuação diária do nível piezométrico usando o método de balanço de energia &#8211; Razão de Bowen. Para tal fim, foram construídos cinco poços e uma torre de monitoramento em uma área de zona ripária da bacia hidrográfica do Ribeirão da Onça (Brotas, São Paulo). Os dados dos poços e da torre de monitoramento foram coletados, a cada 15 minutos, no período de, respectivamente, abril de 2018 e junho de 2018, a janeiro de 2019. Para o processamento dos dados, foi feito um programa em linguagem Python. Nos dados do método de balanço de energia Razão de Bowen foram utilizados o critério de propagação de erros para a rejeição de estimativas, e o método de amostragem direta para a posterior reconstrução da série temporal. No período seco e chuvoso, as taxas médias de ET obtidas pelo método de balanço de energia &#8211; Razão de Bowen foram, respectivamente, de 3,62 &#177; 0,93 mm/dia e 5,09 &#177; 2,34 mm/dia. Entre os métodos baseados na flutuação diária do nível piezométrico, o método de Gribovski apresentou as melhores métricas na avaliação (<font style=\"text-decoration: overline;\"> &#961; = 0.69, <font style=\"text-decoration: overline;\"> &#964;s = 0.55, <font style=\"text-decoration: overline;\"> MAE = 1.77 mm/dia, <font style=\"text-decoration: overline;\"> RMSE = 2.07 mm/dia e <font style=\"text-decoration: overline;\"> MBE = 1.63 mm/dia), o qual mostra o potencial desse tipo de métodos para estimar a ET em zonas ripárias. / Evapotranspiration rate (ET) represents a significant percentage of precipitation in the water balance. At the riparian zones, ET slightly increases due to high water availability. Although there are available methods to ET estimation, such as the based on groundwater level variation, few studies have developed because of theorical complexity, high equipment cost and narrow band of the riparian zones. Thus, this work aims to evaluate 10 groundwater level variation methods using the energy balance &#8211; Bowen ratio method. For that, five wells and one monitoring tower were installed in a riparian zone of the Onça Creek basin (Brotas, São Paulo, Brazil). Data from wells and monitoring tower were collected at each 15 minutes from, respectively, April/2018 and June/2018 to January/2019. For data processing, a Python languague programme was developed. Error propagation method was applied to reject unreliable estimation of ET. Also, direct sampling was used to temporal serie rebuilding. The ET estimations from Bowen ration method range from 3,62 &#177; 0,93 mm/day and 5,09 &#177; 2,34 mm/day (dry and wet period, respectively). Among the groundwater level variation methods, the Gribovski method reached the smallest error (<font style=\"text-decoration: overline;\"> &#961; = 0.69, <font style=\"text-decoration: overline;\"> &#964; s = 0.55, <font style=\"text-decoration: overline;\"> MAE = 1.77 mm/day, <font style=\"text-decoration: overline;\"> RMSE = 2.07 mm/day e <font style=\"text-decoration: overline;\"> MBE = 1.63 mm/day). Then, the Griboski method may be used to ET estimation in riparian zones.

The Geological Survey of Sweden (SGU) has initiated a project to calibrate models to simulategroundwater levels in monitoring wells of their Groundwater Network, based on a commission fromthe Swedish Government after experiencing historically low groundwater levels and shortage in 2016and 2017. A version of the HBV model with 4 parameters, focusing on calculating groundwaterrecharge and levels, was manually calibrated to 119 groundwater stations in 2017 and the modelresults were classified according to a ‘good’, ‘poor’ or ‘bad’ visual fit to observations. In this thesis,the process-based model CoupModel, which allows the user to freely setup a model structure, wasused to simulate groundwater levels. The objectives of this thesis were to evaluate the usability of theCoupModel in groundwater level simulations and forecasting, and compare the results to previoussimulations using the HBV model. 22 groundwater stations of fast and slow responding aquifers, distributed all over Sweden, wereused to simulate groundwater levels with the CoupModel. A model structure with 11 parameters tocalibrate was constructed to represent all groundwater stations. A split-sample test was performed withcalibration of 10,000 Monte Carlo simulations and validation of the 10 simulations with the highestNash-Sutcliffe efficiency (NSE). The NSE performance was highest, and consistent through calibration and validation, for fastresponding aquifers using the CoupModel, whereas the performance of slow responding aquifers waslower. Residual analysis showed periodicity with under- and overestimations for low and highgroundwater levels, respectively, indicating that the model structure is not sufficient in representing allgroundwater stations. No relationship existed between CoupModel performance and HBV calibrationperformance, topographic position, aquifer type, location or distance to climate station. The HBVperformance was lower than for the CoupModel, with residuals of larger spread and periodicity. The CoupModel can be used for simulation and forecasting of groundwater levels, but a newmodel structure or individual structures for all groundwater stations must be constructed. A sensitivityanalysis of the parameters in the model structure must be performed to study the systematic under- andoverestimations. / Grundvatten har en stor betydelse för att upprätthålla ekosystem och försörja människor meddricksvatten, där grundvattentillgång och nivåer beror av bland annat nederbörd, temperatur,snösmältning, växtupptag och antropogen påverkan på jord och mark. Förändringar i temperatur- ochnederbördsmönster på grund av klimatförändringar och en större vattenförbrukning påverkargrundvattennivåernas variationer inom och mellan år. Den här studien syftar till att undersöka hur ochi vilken uträckning den konceptuella modellen CoupModel kan användas för simulering ochprognostisering av grundvattennivåer, samt hur den står sig i relation till en annan, tidigare studeradmodell (HBV-modellen). Studiens relevans uppdagades hos Sveriges geologiska undersökning (SGU)i samband med historiskt låga grundvattennivåer under 2016-2017, genom initiering av ett projekt medmålet att kalibrera grundvattenmodeller till mätstationer i SGUs grundvattennät. Appliceringen avmodeller har stor samhällsnytta då förebyggande av och åtgärder mot låga grundvattennivåer kanplaneras och vidtas utifrån väderprognoser och klimatscenarier. En modellstruktur skapades i CoupModel och användes för att simulera grundvattennivåer i 22grundvattenstationer av olika karaktär och modellen kalibrerades och validerades mot observationer avgrundvattennivå. Resultatet av studien visade att CoupModel kan användas som verktyg försimulering och prognostisering av grundvattennivåer, men att modellstrukturen som användes behöverutvecklas. Systematisk över- och underestimering av observerade nivåer förkommer hos allasimuleringar och ingen relation kunde ses mellan modellens prestation och plats eller typ avgrundvattenstation. CoupModel presterade i de flesta fall bättre än HBV-modellen, men kräversamtidigt mer information om en grundvattenstations jordprofil och fler parametrar att kalibrera.